blackboard vs discipline

blackboard

verb
  • To use a blackboard to assist in an informal discussion. 

noun
  • A large flat surface, finished with black slate or a similar material, that can be written upon with chalk and subsequently erased; a chalkboard. 

discipline

verb
  • To teach someone to obey authority. 

  • To impose order on someone. 

  • To train someone by instruction and practice. 

  • To punish someone in order to (re)gain control. 

noun
  • A flagellation as a means of obtaining sexual gratification. 

  • A specific branch of knowledge or learning. 

  • An enforced compliance or control. 

  • A whip used for self-flagellation. 

  • A category in which a certain art, sport or other activity belongs. 

  • A controlled behaviour; self-control. 

  • A set of rules regulating behaviour. 

  • A punishment to train or maintain control. 

  • A state of order based on submission to authority. 

  • A systematic method of obtaining obedience. 

How often have the words blackboard and discipline occurred in a corpus of books? (source: Google Ngram Viewer )